Global occurrence: Africa (incl Madagascar) | Eurasia – Asia Extratropical | Oceania – Australasia | Eurasia – Europe. Substrate: rock – calcareous, calciferous, basic | rock, stones, pebbles – unspecified. Life habit: lichenized (mutualistic with algal photobionts). Thallus: crustose (crustaceous) – endosubstratal, inconspicuous, immersed | crustose (crustaceous) – episubstratal – unspecified; thallus: continuous, diffuse, effuse | cracked, fissured, fractured, rimose; [th] upper surface: grey(ish) | white(ish) | white(ish) grey | grey(ish) green | grey(ish) white | red(dish) white (pink); [th marginal and upper surface] specific structures: absent; [th] morphol substructures (eg areoles, squamules): discontiguous, dispersed (throughout the thallus); [th] morphol substructures (eg areoles, lobes, branches) upper surface: smooth, plane. Ascomata: absent | present; ascoma: perithecial, perithecioid – hymenial; ascoma [mm]: (low) 0.5 (high) 0.6 (max) 0.8; ascoma: immersed, innate; [ascm, if apoth] margin surface; [if perith] periostiolar area, ostiole, involucrellum: black(ish); [ascm, if apoth] margin excipular photobionts: absent; [ascm, if apoth] subhymenial layers, hypothecium; [if perith] basal excipulum: brown(ish) (if pale: fawn, tan; if mid: cinnamon); [ascm] paraphyses/-oids: absent. Asci: fissitunicate – verrucarialean; [asc] tholus: thickened; [asc] tholus amyloidity (iodine reaction): absent. Ascospores: (median) 8.0; [asp] shape: ellipsoidal; [asp] length [µm]: (min) 20.0 (low) 29.0(median) 31.8 (high) 34.5 (max) 48.0; [asp] width [µm]: (min) 10.0 (low) 16.0(median) 18.0 (high) 20.0 (max) 25.0; [asp] septa: absent – spore lumen unilocular, monolocular; [asp] pigmentation: hyaline, colourless; [asp] perispore, epispore: not apparent | thin, thinly halonate | ornamented, rough, warted, striate, cracked. Secondary metabolites: absent. Primary photobiont: present, chlorophytaceous – trebouxiaceous, chlorococcoid. Secondary photobionts (eg in cephalodia): absent.